101
|
Exposure to Zinc Oxide Nanoparticles Disrupts Endothelial Tight and Adherens Junctions and Induces Pulmonary Inflammatory Cell Infiltration. Int J Mol Sci 2020; 21:ijms21103437. [PMID: 32414036 PMCID: PMC7279309 DOI: 10.3390/ijms21103437] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 04/27/2020] [Accepted: 05/11/2020] [Indexed: 12/19/2022] Open
Abstract
Zinc oxide nanoparticles (ZnONPs) are frequently encountered nanomaterials in our daily lives. Despite the benefits of ZnONPs in a variety of applications, many studies have shown potential health hazards of exposure to ZnONPs. We have shown that oropharyngeal aspiration of ZnONPs in mice increases lung inflammation. However, the detailed mechanisms underlying pulmonary inflammatory cell infiltration remain to be elucidated. Endothelium functions as a barrier between the blood stream and the blood vessel wall. Endothelial barrier dysfunction may increase infiltration of immune cells into the vessel wall and underlying tissues. This current study examined the effects of ZnONPs exposure on endothelial barriers. ZnONPs exposure increased leukocyte infiltration in the mouse lungs. In endothelial cells, ZnONPs reduced the continuity of tight junction proteins claudin-5 and zonula occludens-1 (ZO-1) at the cell junctions. ZnONPs induced adherens junction protein VE-cadherin internalization from membrane to cytosol and dissociation with β-catenin, leading to reduced and diffused staining of VE-cadherin and β-catenin at cell junctions. Our results demonstrated that ZnONPs disrupted both tight and adherens junctions, compromising the integrity and stability of the junction network, leading to inflammatory cell infiltration. Thus, ZnONPs exposure in many different settings should be carefully evaluated for vascular effects and subsequent health impacts.
Collapse
|
102
|
Lynn KS, Peterson RJ, Koval M. Ruffles and spikes: Control of tight junction morphology and permeability by claudins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183339. [PMID: 32389670 DOI: 10.1016/j.bbamem.2020.183339] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/24/2020] [Accepted: 05/01/2020] [Indexed: 02/06/2023]
Abstract
Epithelial barrier function is regulated by a family of transmembrane proteins known as claudins. Functional tight junctions are formed when claudins interact with other transmembrane proteins, cytosolic scaffold proteins and the actin cytoskeleton. The predominant scaffold protein, zonula occludens-1 (ZO-1), directly binds to most claudin C-terminal domains, crosslinking them to the actin cytoskeleton. When imaged by immunofluorescence microscopy, tight junctions most frequently are linear structures that form between tricellular junctions. However, tight junctions also adapt non-linear architectures exhibiting either a ruffled or spiked morphology, which both are responses to changes in claudin engagement of actin filaments. Other terms for ruffled tight junctions include wavy, tortuous, undulating, serpentine or zig-zag junctions. Ruffling is under the control of hypoxia induced factor (HIF) and integrin-mediated signaling, as well as direct mechanical stimulation. Tight junction ruffling is specifically enhanced by claudin-2, antagonized by claudin-1 and requires claudin binding to ZO-1. Tight junction spikes are sites of active vesicle budding and fusion that appear as perpendicular projections oriented towards the nucleus. Spikes share molecular features with focal adherens junctions and tubulobulbar complexes found in Sertoli cells. Lung epithelial cells under stress form spikes due to an increase in claudin-5 expression that directly disrupts claudin-18/ZO-1 interactions. Together this suggests that claudins are not simply passive cargoes controlled by scaffold proteins. We propose a model where claudins specifically influence tight junction scaffold proteins to control interactions with the cytoskeleton as a mechanism that regulates tight junction assembly and function.
Collapse
Affiliation(s)
- K Sabrina Lynn
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Raven J Peterson
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Koval
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
103
|
Targeting zonulin and intestinal epithelial barrier function to prevent onset of arthritis. Nat Commun 2020; 11:1995. [PMID: 32332732 PMCID: PMC7181728 DOI: 10.1038/s41467-020-15831-7] [Citation(s) in RCA: 229] [Impact Index Per Article: 57.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 03/24/2020] [Indexed: 02/05/2023] Open
Abstract
Gut microbial dysbiosis is associated with the development of autoimmune disease, but the mechanisms by which microbial dysbiosis affects the transition from asymptomatic autoimmunity to inflammatory disease are incompletely characterized. Here, we identify intestinal barrier integrity as an important checkpoint in translating autoimmunity to inflammation. Zonulin family peptide (zonulin), a potent regulator for intestinal tight junctions, is highly expressed in autoimmune mice and humans and can be used to predict transition from autoimmunity to inflammatory arthritis. Increased serum zonulin levels are accompanied by a leaky intestinal barrier, dysbiosis and inflammation. Restoration of the intestinal barrier in the pre-phase of arthritis using butyrate or a cannabinoid type 1 receptor agonist inhibits the development of arthritis. Moreover, treatment with the zonulin antagonist larazotide acetate, which specifically increases intestinal barrier integrity, effectively reduces arthritis onset. These data identify a preventive approach for the onset of autoimmune disease by specifically targeting impaired intestinal barrier function. Intestinal dysbiosis is associated with an ever-growing list of autoimmune diseases. Here the authors show that both mice and humans with autoimmune arthritis can have dysbiosis and barrier leakiness prior to major signs of inflammatory arthritis, and treatment of mice with a zonulin antagonist can limit collagen-induced arthritis.
Collapse
|
104
|
Shi Y, Li R, Yang J, Li X. No tight junctions in tight junction protein-1 expressing HeLa and fibroblast cells. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2020; 12:70-78. [PMID: 32419902 PMCID: PMC7218737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/08/2020] [Indexed: 06/11/2023]
Abstract
Tight junctions are important structures that form the barrier of cells and tissues, and they play key roles in maintaining homeostasis of our body. The backbone of the tight junction proteins are claudins, which composed more than twenty members. The tight junction protein 1 (TJP1), also called ZO-1 (Zonula Occludens-1), is one of the tight junction related proteins, and it is widely used in literature to label tight junctions. Here we showed that TJP1 (ZO-1) is highly expressed in cancerous HeLa cells, fibroblast cells, HUVEC as well as MDCK cells, while claudin-1 is highly expressed in HUVEC and MDCK cells, but not expressed in HeLa and fibroblast cells. We aimed to investigate whether tight junction is present in HeLa and fibroblast cells. We used transepithelial/transendothelial electrical resistance (TEER) to measure tight junction dynamics in these cells. The results showed that there is no TEERs in HeLa and fibroblast cells, while there is relatively high TEER in HUVEC and MDCK cells. Importantly, the TEER in MDCK cells is dramatically reduced after knockdown of TJP1 (ZO-1). These results suggest that TJP1 (ZO-1) cannot be used as a marker of tight junctions in a variety of cells, while TJP1 (ZO-1) may play an important role in regulation of tight junctions in MDCK cells.
Collapse
Affiliation(s)
- Yumeng Shi
- Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University83 Fenyang Road, Shanghai 200031, People’s Republic of China
| | - Rongqiang Li
- Department of Urology, Weihaiwei HospitalWeihai, Shandong, China
| | - Jin Yang
- Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University83 Fenyang Road, Shanghai 200031, People’s Republic of China
| | - Xinbo Li
- Ophthalmology, Casey Eye Institute, Oregon Health & Science UniversityPortland, Oregon, USA
| |
Collapse
|
105
|
Tight Junctions as Targets and Effectors of Mucosal Immune Homeostasis. Cell Mol Gastroenterol Hepatol 2020; 10:327-340. [PMID: 32304780 PMCID: PMC7326733 DOI: 10.1016/j.jcmgh.2020.04.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/28/2020] [Accepted: 04/03/2020] [Indexed: 12/11/2022]
Abstract
Defective epithelial barrier function is present in maladies including epidermal burn injury, environmental lung damage, renal tubular disease, and a range of immune-mediated and infectious intestinal disorders. When the epithelial surface is intact, the paracellular pathway between cells is sealed by the tight junction. However, permeability of tight junctions varies widely across tissues and can be markedly impacted by disease. For example, tight junctions within the skin and urinary bladder are largely impermeant and their permeability is not regulated. In contrast, tight junctions of the proximal renal tubule and intestine are selectively permeable to water and solutes on the basis of their biophysical characteristics and, in the gut, can be regulated by the immune system with remarkable specificity. Conversely, modulation of tight junction barrier conductance, especially within the gastrointestinal tract, can impact immune homeostasis and diverse pathologies. Thus, tight junctions are both effectors and targets of immune regulation. Using the gastrointestinal tract as an example, this review explores current understanding of this complex interplay between tight junctions and immunity.
Collapse
|
106
|
Xie Y, Yan L, Zeng H, Chen W, Lu JH, Wan JB, Su H, Yao X. Fish oil protects the blood-brain barrier integrity in a mouse model of Alzheimer's disease. Chin Med 2020; 15:29. [PMID: 32256685 PMCID: PMC7106819 DOI: 10.1186/s13020-020-00314-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/19/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is ranked as the most prevalent neurodegenerative disease. However, the exact molecular mechanisms underlying pathophysiological alterations in AD remain unclear, especially at the prodromal stage. The decreased proteolytic degradation of Aβ, blood-brain barrier (BBB) disruption, and neuroinflammation are considered to play key roles in the course of AD. METHODS Male APPswe/PS1dE9 C57BL/6 J double-transgenic (APP/PS1) mice in the age range from 1 month to 6 months and age-matched wild type mice were used in this study, intending to investigate the expression profiles of Aβ-degrading enzymes for Aβ degradation activities and zonula occludens-1 (zo-1) for BBB integrity at the prodromal stage. RESULTS Our results showed that there were no significant genotype-related alterations in mRNA expression levels of 4 well-characterized Aβ-degrading enzymes in APP/PS1 mice within the ages of 6 months. Interestingly, a significant decrease in zo-1 expression was observed in APP/PS1 mice starting from the age of 5 months, suggesting that BBB disrupt occurs at an early stage. Moreover, treatment of fish oil (FO) for 4 weeks remarkably increased zo-1 expression and significantly inhibited the glial activation and NF-κB activation in APP/PS1 mice. CONCLUSION The results of our study suggest that FO supplement could be a potential therapeutic early intervention for AD through protecting the BBB integrity and suppressing glial and NF-κB activation.
Collapse
Affiliation(s)
- Youna Xie
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical, Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080 China
| | - Lingli Yan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Haitao Zeng
- Center for Reproductive Medicine, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080 People’s Republic of China
| | - Weineng Chen
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical, Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080 China
| | - Jia-Hong Lu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Jian-Bo Wan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Huanxing Su
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Xiaoli Yao
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical, Department and Key Discipline of Neurology, No.58 Zhongshan Road 2, Guangzhou, 510080 China
| |
Collapse
|
107
|
González-Mariscal L, Miranda J, Gallego-Gutiérrez H, Cano-Cortina M, Amaya E. Relationship between apical junction proteins, gene expression and cancer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183278. [PMID: 32240623 DOI: 10.1016/j.bbamem.2020.183278] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 01/09/2020] [Accepted: 03/06/2020] [Indexed: 12/11/2022]
Abstract
The apical junctional complex (AJC) is a cell-cell adhesion system present at the upper portion of the lateral membrane of epithelial cells integrated by the tight junction (TJ) and the adherens junction (AJ). This complex is crucial to initiate and stabilize cell-cell adhesion, to regulate the paracellular transit of ions and molecules and to maintain cell polarity. Moreover, we now consider the AJC as a hub of signal transduction that regulates cell-cell adhesion, gene transcription and cell proliferation and differentiation. The molecular components of the AJC are multiple and diverse and depending on the cellular context some of the proteins in this complex act as tumor suppressors or as promoters of cell transformation, migration and metastasis outgrowth. Here, we describe these new roles played by TJ and AJ proteins and their potential use in cancer diagnostics and as targets for therapeutic intervention.
Collapse
Affiliation(s)
- Lorenza González-Mariscal
- Department of Physiology, Biophysics and Neuroscience, Center of Research and Advanced Studies (Cinvestav), Mexico City, Mexico.
| | - Jael Miranda
- Department of Physiology, Biophysics and Neuroscience, Center of Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Helios Gallego-Gutiérrez
- Department of Physiology, Biophysics and Neuroscience, Center of Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Misael Cano-Cortina
- Department of Physiology, Biophysics and Neuroscience, Center of Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Elida Amaya
- Department of Physiology, Biophysics and Neuroscience, Center of Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| |
Collapse
|
108
|
Zhang L, Wang F, Wang J, Wang Y, Fang Y. Intestinal fatty acid-binding protein mediates atherosclerotic progress through increasing intestinal inflammation and permeability. J Cell Mol Med 2020; 24:5205-5212. [PMID: 32220004 PMCID: PMC7205806 DOI: 10.1111/jcmm.15173] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 01/06/2020] [Accepted: 02/06/2020] [Indexed: 12/15/2022] Open
Abstract
Atherosclerosis is one of leading phenotypes of cardiovascular diseases, featured with increased vascular intima‐media thickness (IMT) and unstable plaques. The interaction between gastrointestinal system and cardiovascular homeostasis is emerging as a hot topic. Therefore, the present study aimed to explore the role of an intestinal protein, intestinal fatty acid‐binding protein (I‐FABP/FABP2) in the atherosclerotic progress. In western diet–fed ApoE−/− mice, FABP2 was highly expressed in intestine. Silence of intestinal Fabp2 attenuated western diet–induced atherosclerotic phenotypes, including decreasing toxic lipid accumulation, vascular fibrosis and inflammatory response. Mechanistically, intestinal Fabp2 knockdown improved intestinal permeability through increasing the expression of tight junction proteins. Meanwhile, intestinal Fabp2 knockdown mice exhibited down‐regulation of intestinal inflammation in western diet–fed ApoE−/− mice. In clinical patients, the circulating level of FABP2 was obviously increased in patients with cardiovascular disease and positively correlated with the value of carotid intima‐media thickness, total cholesterol and triglyceride. In conclusion, FABP2‐induced intestinal permeability could address a potential role of gastrointestinal system in the development of atherosclerosis, and targeting on intestinal FABP2 might provide a therapeutic approach to protect against atherosclerosis.
Collapse
Affiliation(s)
- Lulu Zhang
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, China.,The Key Laboratory of Myocardial Ischemia, Harbin Medical University, Ministry of Education, Harbin, China
| | - Fan Wang
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, China.,The Key Laboratory of Myocardial Ischemia, Harbin Medical University, Ministry of Education, Harbin, China
| | - Jiajun Wang
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, China.,The Key Laboratory of Myocardial Ischemia, Harbin Medical University, Ministry of Education, Harbin, China
| | - Yongshun Wang
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, China.,The Key Laboratory of Myocardial Ischemia, Harbin Medical University, Ministry of Education, Harbin, China
| | - Yan Fang
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, China.,The Key Laboratory of Myocardial Ischemia, Harbin Medical University, Ministry of Education, Harbin, China
| |
Collapse
|
109
|
Putative Receptors for Gravity Sensing in Mammalian Cells: The Effects of Microgravity. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10062028] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Gravity is a constitutive force that influences life on Earth. It is sensed and translated into biochemical stimuli through the so called “mechanosensors”, proteins able to change their molecular conformation in order to amplify external cues causing several intracellular responses. Mechanosensors are widely represented in the human body with important structures such as otholiths in hair cells of vestibular system and statoliths in plants. Moreover, they are also present in the bone, where mechanical cues can cause bone resorption or formation and in muscle in which mechanical stimuli can increase the sensibility for mechanical stretch. In this review, we discuss the role of mechanosensors in two different conditions: normogravity and microgravity, emphasizing their emerging role in microgravity. Microgravity is a singular condition in which many molecular changes occur, strictly connected with the modified gravity force and free fall of bodies. Here, we first summarize the most important mechanosensors involved in normogravity and microgravity. Subsequently, we propose muscle LIM protein (MLP) and sirtuins as new actors in mechanosensing and signaling transduction under microgravity.
Collapse
|
110
|
Cornu R, Chrétien C, Pellequer Y, Martin H, Béduneau A. Small silica nanoparticles transiently modulate the intestinal permeability by actin cytoskeleton disruption in both Caco-2 and Caco-2/HT29-MTX models. Arch Toxicol 2020; 94:1191-1202. [PMID: 32162006 DOI: 10.1007/s00204-020-02694-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/02/2020] [Indexed: 01/08/2023]
Abstract
Amorphous silica nanoparticles are widely used as pharmaceutical excipients and food additive (E551). Despite the potential human health risks of mineral nanoparticles, very few data regarding their oral toxicity are currently available. This study aims to evaluate and to understand the interactions of silica particles at 1 and 10 mg mL-1 with the intestinal barrier using a Caco-2 monolayer and a Caco-2/HT29-MTX co-culture. A size- and concentration-dependent reversible increase of the paracellular permeability is identified after a short-term exposure to silica nanoparticles. Nanoparticles of 30 nm induce the highest transepithelial electrical resistance drop whereas no effect is observed with 200 nm particles. Additive E551 affect the Caco-2 monolayer permeability. Mucus layer reduces the permeability modulation by limiting the cellular uptake of silica. After nanoparticle exposure, tight junction expression including Zonula occludens 1 (ZO-1) and Claudin 2 is not affected, whereas the actin cytoskeleton disruption of enterocytes and the widening of ZO-1 staining bands are observed. A complete permeability recovery is concomitant with the de novo filament actin assembly and the reduction of ZO-1 bands. These findings suggest the paracellular modulation by small silica particles is directly correlated to the alteration of the ZO-actin binding strongly involved in the stability of the tight junction network.
Collapse
Affiliation(s)
- Raphaël Cornu
- PEPITE EA4267, FHU Increase, Univ. Bourgogne Franche-Comté, 25000, Besançon, France
| | - Claire Chrétien
- PEPITE EA4267, FHU Increase, Univ. Bourgogne Franche-Comté, 25000, Besançon, France
| | - Yann Pellequer
- PEPITE EA4267, FHU Increase, Univ. Bourgogne Franche-Comté, 25000, Besançon, France
| | - Hélène Martin
- PEPITE EA4267, FHU Increase, Univ. Bourgogne Franche-Comté, 25000, Besançon, France
| | - Arnaud Béduneau
- PEPITE EA4267, FHU Increase, Univ. Bourgogne Franche-Comté, 25000, Besançon, France.
| |
Collapse
|
111
|
Bao H, Yang S, Li H, Yao H, Zhang Y, Zhang J, Xu G, Jin H, Wang F. The Interplay Between E-Cadherin, Connexin 43, and Zona Occludens 1 in Retinal Pigment Epithelial Cells. Invest Ophthalmol Vis Sci 2020; 60:5104-5111. [PMID: 31826237 DOI: 10.1167/iovs.19-27768] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Cell-cell contact in retinal pigment epithelium (RPE) involves adherent junctions, gap junctions, and tight junctions, which are primarily composed by E-cadherin, zona occludens 1 (ZO-1), and connexin 43, respectively. Here, we aimed to explore the relationship and interplay between these junction-associated proteins. Methods E-cadherin, connexin 43, and ZO-1 expression in human primary RPE in the early phase after TGF-β1 stimulation was detected. The knockdown of E-cadherin, ZO-1, and connexin 43 was performed to characterize the regulatory network involving these three proteins. Dye transfer and FITC-dextran permeability assays were conducted to observe the epithelial functional alterations. Transmission electron microscopy (TEM) was used to observe the ultrastructure of the cell-cell junctions in mouse RPE. The immunofluorescence staining and coimmunoprecipitation were performed to observe the colocalization and the physical association of E-cadherin, ZO-1, and connexin 43. Results Among these three components, E-cadherin appeared to be the first protein that was downregulated after TGF-β1 treatment. The ultrastructures of adherent junctions, gap junctions, and tight junctions could be observed in mouse RPE by TEM. E-cadherin, ZO-1, and connexin 43 were colocalized and physically bound to each other. The knockdown of one of these three proteins led to downregulation of the other two proteins and compromised epithelial function. Conclusions E-cadherin, ZO-1, and connexin 43 were physically associated with each other and were mutually regulated. To enhance the understanding of cell-cell contacts, a holistic view is needed. Our results provide new insights in RPE disorders such as proliferative vitreoretinopathy.
Collapse
Affiliation(s)
- Huiqian Bao
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China.,School of Medicine, Nanchang University, Nanchang, Jiangxi Province, China
| | - Shuai Yang
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Hui Li
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Haipei Yao
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Yao Zhang
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Jingfa Zhang
- Department of Ophthalmology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Guotong Xu
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Haiying Jin
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Fang Wang
- Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| |
Collapse
|
112
|
Abstract
Epithelial cells form highly organized polarized sheets with characteristic cell morphologies and tissue architecture. Cell–cell adhesion and intercellular communication are prerequisites of such cohesive sheets of cells, and cell connectivity is mediated through several junctional assemblies, namely desmosomes, adherens, tight and gap junctions. These cell–cell junctions form signalling hubs that not only mediate cell–cell adhesion but impact on multiple aspects of cell behaviour, helping to coordinate epithelial cell shape, polarity and function. This review will focus on the tight and adherens junctions, constituents of the apical junctional complex, and aims to provide a comprehensive overview of the complex signalling that underlies junction assembly, integrity and plasticity.
Collapse
Affiliation(s)
- Alexandra D Rusu
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
| | - Marios Georgiou
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, UK
| |
Collapse
|
113
|
Manning L, Holmes J, Bonin K, Vidi PA. Radial Profile Analysis of Epithelial Polarity in Breast Acini: A Tool for Primary (Breast) Cancer Prevention. Front Med (Lausanne) 2020; 6:314. [PMID: 31998733 PMCID: PMC6970192 DOI: 10.3389/fmed.2019.00314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 12/11/2019] [Indexed: 11/13/2022] Open
Abstract
Preventing cancer is vastly better than treating the disease in terms of a patient's quality of life and healthcare costs. Yet, to screen for chemopreventative drugs or evaluate interventions aimed at lowering cancer risk, quantitative readouts of risk are needed. In the breast and in other organs of epithelial origin, apical-basal polarity is key to homeostasis and is one of the first tissue characteristics lost during cancer initiation. Therefore, apical-basal polarity may be leveraged as an "architectural" determinant of cancer risk. A classic approach to quantify the localization of epithelial polarity markers is visual scoring at the microscope by trained investigators. This approach is time-intensive and limited to low throughput. To increase the speed, accuracy, and scoring volume, we developed an algorithm that essentially replaces the human eye to objectively quantify epithelial polarity in microscopy images of breast glandular units (acini). Acini in culture are identified based on a nuclear stain and the corresponding masks are divided into concentric terraces of equal width. This positional information is used to calculate radial intensity profiles (RP) of polarity markers. Profiles with a steep slope represent polarized structures, whereas more horizontal curves are indicative of non-polarized acini. To compare treatment effects, RP curves are integrated into summary values of polarity. We envision applications of this method for primary cancer prevention research with acini organoids, specifically (1) to screen for chemoprevention drugs, (2) for toxicological assessment of suspected carcinogens and pharmacological hit compounds, and (3) for personalized evaluation of cancer risk and risk-reducing interventions. The RadialProfiler algorithm developed for the MATLAB computing environment and for users without prior informatics knowledge is publicly available on the Open Science Framework (OSF).
Collapse
Affiliation(s)
- Lawton Manning
- Department of Physics, Wake Forest University, Winston-Salem, NC, United States
| | - Julia Holmes
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Keith Bonin
- Department of Physics, Wake Forest University, Winston-Salem, NC, United States.,Comprehensive Cancer Center of Wake Forest University, Winston-Salem, NC, United States
| | - Pierre-Alexandre Vidi
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC, United States.,Comprehensive Cancer Center of Wake Forest University, Winston-Salem, NC, United States
| |
Collapse
|
114
|
Khalyfa A, Gozal D, Chan WC, Andrade J, Prasad B. Circulating plasma exosomes in obstructive sleep apnoea and reverse dipping blood pressure. Eur Respir J 2020; 55:13993003.01072-2019. [PMID: 31672757 DOI: 10.1183/13993003.01072-2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 10/12/2019] [Indexed: 12/27/2022]
Abstract
BACKGROUND Obstructive sleep apnoea (OSA) increases the risk of an abnormal nondipping 24 h blood pressure profile, an independent risk factor for cardiovascular disease (CVD). We examined differential exosomal microRNA (miRNA) expression in untreated OSA patients with normal dipping blood pressure (NDBP) and reverse dipping blood pressure (RDBP), an extreme form of nondipping, to understand the mechanisms underlying nondipping blood pressure in OSA. METHODS 46 patients (15 RDBP versus 31 NDBP) matched for OSA severity (respiratory event index 32.6±22.5 versus 32.2±18.1 events·h-1; p=0.9), age (54.8±12.9 versus 49±9.9 years; p=0.09) and body mass index (36.2±6.6 versus 34.4±6.8 kg·m-2; p=0.4) were included. Plasma exosomes were characterised by flow cytometry and functional in vitro reporter assays were conducted on cultured endothelial cells. Exosome miRNA cargo was profiled with microarrays followed by bioinformatics analyses. RESULTS Exosomes from RDBP patients increased the permeability of endothelial cell tight junctions and adhesion molecule expression. Principal component analyses of miRNA array data showed strict separation and identification of the two groups. A restricted and validated signature of exosomal miRNAs was identified in the RDBP versus NDBP group. Their predicted target genes involved phosphatidylinositol 3-kinase-Akt (p=0.004), Ras (p=3.42E-05), Wnt (p=0.003) and hypoxia inducible factor-1 signalling (p=0.04), inflammatory mediator regulation of transient receptor potential channels (p=0.01), and several cancer-related pathways. CONCLUSIONS Patients with RDBP have altered miRNA cargoes in circulating exosomes that invoke in vitro endothelial dysfunction. A selected number of circulating exosomal miRNAs play an important role in abnormal circadian regulation of blood pressure and may provide prognostic biomarkers of CVD risk in OSA.
Collapse
Affiliation(s)
- Abdelnaby Khalyfa
- Dept of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO, USA
| | - David Gozal
- Dept of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO, USA
| | - Wen-Ching Chan
- Center for Research Informatics, The University of Chicago, Chicago, IL, USA
| | - Jorge Andrade
- Center for Research Informatics, The University of Chicago, Chicago, IL, USA
| | - Bharati Prasad
- Division of Pulmonary, Critical Care, Sleep and Allergy, Dept of Medicine, University of Illinois at Chicago and Jesse Brown VA Medical Center, Chicago, IL, USA
| |
Collapse
|
115
|
Zhang Y, Zhao Y, Wu Y, Qi J, Li F, Kou J, Yu B. Ophiopogon Saponin C1 Inhibits Lung Tumors by Stabilizing Endothelium Permeability via Inhibition of PKCδ. Int J Biol Sci 2020; 16:396-407. [PMID: 32015677 PMCID: PMC6990896 DOI: 10.7150/ijbs.34978] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 11/12/2019] [Indexed: 11/13/2022] Open
Abstract
As the most frequent cause of cancer-related death worldwide, lung cancer is closely related to inflammation. The interaction between tumor cells and inflammatory cells promotes tumor development and metastasis. During tumor development, vascular endothelial cells form the most important barrier to prevent tumor cell migration to the blood and tissue. Increased vascular permeability provides favorable conditions for the migration of tumor cells, and endothelial tight junctions are an important component of the vascular barrier. Protein kinase C δ is involved in the occurrence of non-small cell lung cancer and regulates vascular permeability and tight junction protein expression. Src kinase was reported to play an important role in TNF-α-induced endothelial inflammation. Ophiopogon Saponin C1 is a new chemical compound isolated from Liriope muscari, but its pharmacological activities have not been fully elucidated. Therefore, we tested the protective effects of C1 on endothelial permeability in a model of TNF-α-induced endothelial inflammation by transendothelial electrical resistance and sodium fluorescein assays and verified these results in a nude mouse model of experimental pulmonary adenocarcinoma metastasis. We further elucidated the mechanism of C1, which was based on the PKCδ and Src proteins, by Western blotting. C1 can inhibit lung cancer in vivo, regulate the level of plasma inflammation in tumor-bearing mice, and protect the pulmonary vascular barrier against injury induced by cancer. It was investigated the expression and distribution of the TJ index protein ZO-1 in mouse vascular endothelium and HUVECs and found that C1 could inhibit the degradation and breakage of the ZO-1 protein. Related signaling experiments confirmed that C1 can inhibit TNF-α and activation of PKCδ and Src kinase. This study laid the foundation for further analysis of new drugs with clear mechanisms and independent intellectual property rights of traditional Chinese medicines.
Collapse
Affiliation(s)
| | | | | | | | | | - Junping Kou
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Longmian Road, Nanjing 211198, China
| | - Boyang Yu
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Longmian Road, Nanjing 211198, China
| |
Collapse
|
116
|
A Simulated Microgravity Environment Causes a Sustained Defect in Epithelial Barrier Function. Sci Rep 2019; 9:17531. [PMID: 31772208 PMCID: PMC6879622 DOI: 10.1038/s41598-019-53862-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 10/31/2019] [Indexed: 02/06/2023] Open
Abstract
Intestinal epithelial cell (IEC) junctions constitute a robust barrier to invasion by viruses, bacteria and exposure to ingested agents. Previous studies showed that microgravity compromises the human immune system and increases enteropathogen virulence. However, the effects of microgravity on epithelial barrier function are poorly understood. The aims of this study were to identify if simulated microgravity alters intestinal epithelial barrier function (permeability), and susceptibility to barrier-disrupting agents. IECs (HT-29.cl19a) were cultured on microcarrier beads in simulated microgravity using a rotating wall vessel (RWV) for 18 days prior to seeding on semipermeable supports to measure ion flux (transepithelial electrical resistance (TER)) and FITC-dextran (FD4) permeability over 14 days. RWV cells showed delayed apical junction localization of the tight junction proteins, occludin and ZO-1. The alcohol metabolite, acetaldehyde, significantly decreased TER and reduced junctional ZO-1 localization, while increasing FD4 permeability in RWV cells compared with static, motion and flask control cells. In conclusion, simulated microgravity induced an underlying and sustained susceptibility to epithelial barrier disruption upon removal from the microgravity environment. This has implications for gastrointestinal homeostasis of astronauts in space, as well as their capability to withstand the effects of agents that compromise intestinal epithelial barrier function following return to Earth.
Collapse
|
117
|
Cong X, Kong W. Endothelial tight junctions and their regulatory signaling pathways in vascular homeostasis and disease. Cell Signal 2019; 66:109485. [PMID: 31770579 DOI: 10.1016/j.cellsig.2019.109485] [Citation(s) in RCA: 132] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/21/2019] [Accepted: 11/21/2019] [Indexed: 12/13/2022]
Abstract
Endothelial tight junctions (TJs) regulate the transport of water, ions, and molecules through the paracellular pathway, serving as an important barrier in blood vessels and maintaining vascular homeostasis. In endothelial cells (ECs), TJs are highly dynamic structures that respond to multiple external stimuli and pathological conditions. Alterations in the expression, distribution, and structure of endothelial TJs may lead to many related vascular diseases and pathologies. In this review, we provide an overview of the assessment methods used to evaluate endothelial TJ barrier function both in vitro and in vivo and describe the composition of endothelial TJs in diverse vascular systems and ECs. More importantly, the direct phosphorylation and dephosphorylation of TJ proteins by intracellular kinases and phosphatases, as well as the signaling pathways involved in the regulation of TJs, including and the protein kinase C (PKC), PKA, PKG, Ras homolog gene family member A (RhoA), mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K)/Akt, and Wnt/β-catenin pathways, are discussed. With great advances in this area, targeting endothelial TJs may provide novel treatment for TJ-related vascular pathologies.
Collapse
Affiliation(s)
- Xin Cong
- Department of Physiology and Pathophysiology, Peking University School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China.
| | - Wei Kong
- Department of Physiology and Pathophysiology, Peking University School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing 100191, China.
| |
Collapse
|
118
|
Varadarajan S, Stephenson RE, Miller AL. Multiscale dynamics of tight junction remodeling. J Cell Sci 2019; 132:132/22/jcs229286. [PMID: 31754042 DOI: 10.1242/jcs.229286] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Epithelial cells form tissues that generate biological barriers in the body. Tight junctions (TJs) are responsible for maintaining a selectively permeable seal between epithelial cells, but little is known about how TJs dynamically remodel in response to physiological forces that challenge epithelial barrier function, such as cell shape changes (e.g. during cell division) or tissue stretching (e.g. during developmental morphogenesis). In this Review, we first introduce a framework to think about TJ remodeling across multiple scales: from molecular dynamics, to strand dynamics, to cell- and tissue-scale dynamics. We then relate knowledge gained from global perturbations of TJs to emerging information about local TJ remodeling events, where transient localized Rho activation and actomyosin-mediated contraction promote TJ remodeling to repair local leaks in barrier function. We conclude by identifying emerging areas in the field and propose ideas for future studies that address unanswered questions about the mechanisms that drive TJ remodeling.
Collapse
Affiliation(s)
- Saranyaraajan Varadarajan
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, United States
| | - Rachel E Stephenson
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, United States
| | - Ann L Miller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, United States
| |
Collapse
|
119
|
Venugopal S, Anwer S, Szászi K. Claudin-2: Roles beyond Permeability Functions. Int J Mol Sci 2019; 20:ijms20225655. [PMID: 31726679 PMCID: PMC6888627 DOI: 10.3390/ijms20225655] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 11/08/2019] [Accepted: 11/09/2019] [Indexed: 12/12/2022] Open
Abstract
Claudin-2 is expressed in the tight junctions of leaky epithelia, where it forms cation-selective and water permeable paracellular channels. Its abundance is under fine control by a complex signaling network that affects both its synthesis and turnover in response to various environmental inputs. Claudin-2 expression is dysregulated in many pathologies including cancer, inflammation, and fibrosis. Claudin-2 has a key role in energy-efficient ion and water transport in the proximal tubules of the kidneys and in the gut. Importantly, strong evidence now also supports a role for this protein as a modulator of vital cellular events relevant to diseases. Signaling pathways that are overactivated in diseases can alter claudin-2 expression, and a good correlation exists between disease stage and claudin-2 abundance. Further, loss- and gain-of-function studies showed that primary changes in claudin-2 expression impact vital cellular processes such as proliferation, migration, and cell fate determination. These effects appear to be mediated by alterations in key signaling pathways. The specific mechanisms linking claudin-2 to these changes remain poorly understood, but adapters binding to the intracellular portion of claudin-2 may play a key role. Thus, dysregulation of claudin-2 may contribute to the generation, maintenance, and/or progression of diseases through both permeability-dependent and -independent mechanisms. The aim of this review is to provide an overview of the properties, regulation, and functions of claudin-2, with a special emphasis on its signal-modulating effects and possible role in diseases.
Collapse
|
120
|
Otani T, Nguyen TP, Tokuda S, Sugihara K, Sugawara T, Furuse K, Miura T, Ebnet K, Furuse M. Claudins and JAM-A coordinately regulate tight junction formation and epithelial polarity. J Cell Biol 2019; 218:3372-3396. [PMID: 31467165 PMCID: PMC6781433 DOI: 10.1083/jcb.201812157] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 06/14/2019] [Accepted: 07/24/2019] [Indexed: 01/03/2023] Open
Abstract
Tight junctions (TJs) establish the epithelial barrier and are thought to form a membrane fence to regulate epithelial polarity, although the roles of TJs in epithelial polarity remain controversial. Claudins constitute TJ strands in conjunction with the cytoplasmic scaffolds ZO-1 and ZO-2 and play pivotal roles in epithelial barrier formation. However, how claudins and other TJ membrane proteins cooperate to organize TJs remains unclear. Here, we systematically knocked out TJ components by genome editing and show that while ZO-1/ZO-2-deficient cells lacked TJ structures and epithelial barriers, claudin-deficient cells lacked TJ strands and an electrolyte permeability barrier but formed membrane appositions and a macromolecule permeability barrier. Moreover, epithelial polarity was disorganized in ZO-1/ZO-2-deficient cells, but not in claudin-deficient cells. Simultaneous deletion of claudins and a TJ membrane protein JAM-A resulted in a loss of membrane appositions and a macromolecule permeability barrier and in sporadic epithelial polarity defects. These results demonstrate that claudins and JAM-A coordinately regulate TJ formation and epithelial polarity.
Collapse
Affiliation(s)
- Tetsuhisa Otani
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Thanh Phuong Nguyen
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Shinsaku Tokuda
- Division of Nephrology and Hypertension, Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS
| | - Kei Sugihara
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Taichi Sugawara
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Kyoko Furuse
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Takashi Miura
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Klaus Ebnet
- Institute-Associated Research Group "Cell Adhesion and Cell Polarity," Institute of Medical Biochemistry, Zentrum für Molekularbiologie der Entzündung, University of Münster, Münster, Germany
| | - Mikio Furuse
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
- Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| |
Collapse
|
121
|
Abstract
Tight junctions (TJ) play a central role in the homeostasis of epithelial and endothelial tissues, by providing a semipermeable barrier to ions and solutes, by contributing to the maintenance of cell polarity, and by functioning as signaling platforms. TJ are associated with the actomyosin and microtubule cytoskeletons, and the crosstalk with the cytoskeleton is fundamental for junction biogenesis and physiology. TJ are spatially and functionally connected to adherens junctions (AJ), which are essential for the maintenance of tissue integrity. Mechano-sensing and mechano-transduction properties of several AJ proteins have been characterized during the last decade. However, little is known about how mechanical forces act on TJ and their proteins, how TJ control the mechanical properties of cells and tissues, and what are the underlying molecular mechanisms. Here I review recent studies that have advanced our understanding of the relationships between mechanical force and TJ biology.
Collapse
|
122
|
Ugalde-Silva P, Navarro-Garcia F. Coordinated transient interaction of ZO-1 and afadin is required for pedestal maturation induced by EspF from enteropathogenic Escherichia coli. Microbiologyopen 2019; 8:e931. [PMID: 31568664 PMCID: PMC6925160 DOI: 10.1002/mbo3.931] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/14/2019] [Accepted: 08/15/2019] [Indexed: 01/09/2023] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) infection causes a histopathological lesion including recruitment of F‐actin beneath the attached bacteria and formation of actin‐rich pedestal‐like structures. Another important target of EPEC is the tight junction (TJ), and EspF induces displacement of TJ proteins and increased intestinal permeability. Previously, we determined that an EPEC strain lacking EspF did not cause TJ disruption; meanwhile, pedestals were located on the TJ and smaller than those induced by the wild‐type strain. Therefore, EspF could be playing an important role in both phenotypes. Here, using different cell models, we found that EspF was essential for pedestal maturation through ZO‐1 disassembly from TJ, leading to (a) ZO‐1 recruitment to the pedestal structure; no other main TJ proteins were required. Recruited ZO‐1 allowed the afadin recruitment. (b) Afadin recruitment caused an afadin–ZO‐1 transient interaction, like during TJ formation. (c) Afadin and ZO‐1 were segregated to the tip and the stem of pedestal, respectively, causing pedestal maturation. Initiation of these three discrete phases for pedestal maturation functionally and physically required EspF expression. Pedestal maturation process could help coordinate the epithelial actomyosin function by maintaining the actin‐rich column composing the pedestal structure and could be important in the dynamics of the pedestal movement on epithelial cells.
Collapse
Affiliation(s)
- Paul Ugalde-Silva
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México City, Mexico
| | - Fernando Navarro-Garcia
- Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México City, Mexico
| |
Collapse
|
123
|
Succinate Modulates Intestinal Barrier Function and Inflammation Response in Pigs. Biomolecules 2019; 9:biom9090486. [PMID: 31540325 PMCID: PMC6770553 DOI: 10.3390/biom9090486] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 09/04/2019] [Accepted: 09/11/2019] [Indexed: 12/12/2022] Open
Abstract
Succinate is a metabolic intermediate of the tricarboxylic acid (TCA) cycle in all aerobic organisms, and is also a vital microbial metabolite in the gut. Although succinate is known to regulate intestinal metabolism and immune function, its role in the protection of the intestinal epithelial barrier function and inflammation is poorly characterized. In this study, we evaluated the effects of succinate on intestinal epithelial barrier function and inflammation in pigs. Twenty-four growing pigs were distributed into three groups (n = 8) and received either a basal diet (control group) or the same diet supplemented with 0.1% succinate or 1% succinate. The diet supplemented with 1% succinate led to alterations in the intestinal morphology. We confirmed in vitro that 5 mM succinate treatment modulated intestinal epithelial permeability by increased transepithelial electrical resistance (TEER) in intestinal porcine epithelial cell (IPEC)-J2 cells. Furthermore, succinate treatment increased the abundance of tight junction proteins claudin-1, zona occluden (ZO)-1, and ZO-2 in the jejunum in vivo and in vitro. In addition, dietary succinate supplementation promoted the expression of inflammatory cytokines interleukin (IL)-25, IL-10, IL-8, and IL-18 in the jejunum. Taken together, these data identify a novel role of succinate in the modulation of intestinal epithelial barrier function, which may be a nutritional target to improve gut health in animals.
Collapse
|
124
|
ZO-2 Is a Master Regulator of Gene Expression, Cell Proliferation, Cytoarchitecture, and Cell Size. Int J Mol Sci 2019; 20:ijms20174128. [PMID: 31450555 PMCID: PMC6747478 DOI: 10.3390/ijms20174128] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/08/2019] [Accepted: 08/10/2019] [Indexed: 12/13/2022] Open
Abstract
ZO-2 is a cytoplasmic protein of tight junctions (TJs). Here, we describe ZO-2 involvement in the formation of the apical junctional complex during early development and in TJ biogenesis in epithelial cultured cells. ZO-2 acts as a scaffold for the polymerization of claudins at TJs and plays a unique role in the blood–testis barrier, as well as at TJs of the human liver and the inner ear. ZO-2 movement between the cytoplasm and nucleus is regulated by nuclear localization and exportation signals and post-translation modifications, while ZO-2 arrival at the cell border is triggered by activation of calcium sensing receptors and corresponding downstream signaling. Depending on its location, ZO-2 associates with junctional proteins and the actomyosin cytoskeleton or a variety of nuclear proteins, playing a role as a transcriptional repressor that leads to inhibition of cell proliferation and transformation. ZO-2 regulates cell architecture through modulation of Rho proteins and its absence induces hypertrophy due to inactivation of the Hippo pathway and activation of mTOR and S6K. The interaction of ZO-2 with viral oncoproteins and kinases and its silencing in diverse carcinomas reinforce the view of ZO-2 as a tumor regulator protein.
Collapse
|
125
|
Rouaud F, Vasileva E, Spadaro D, Tsukita S, Citi S. R40.76 binds to the α domain of ZO-1: role of ZO-1 (α+) in epithelial differentiation and mechano-sensing. Tissue Barriers 2019; 7:e1653748. [PMID: 31438766 PMCID: PMC6748370 DOI: 10.1080/21688370.2019.1653748] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The barrier function of epithelia and endothelia depends on tight junctions, which are formed by the polymerization of claudins on a scaffold of ZO proteins. Two differentially spliced isoforms of ZO-1 have been described, depending on the presence of the α domain, but the function of this domain is unclear. ZO-1 also contains a C-terminal ZU5 domain, which is involved in a mechano-sensitive intramolecular interaction with the central (ZPSG) region of ZO-1. Here we use immunoblotting and immunofluorescence to map the binding sites for commercially available monoclonal and polyclonal antibodies against ZO-1, and for a new polyclonal antibody (R3) that we developed against the ZO-1 C-terminus. We demonstrate that antibody R40.76 binds to the α domain, and the R3 antibody binds to the ZU5 domain. The (α+) isoform of ZO-1 shows higher expression in epithelial versus endothelial cells, and in differentiated versus undifferentiated primary keratinocytes, suggesting a link to epithelial differentiation and a potential molecular adaptation to junctions subjected to stronger mechanical forces. These results provide new tools and hypotheses to investigate the role of the α and ZU5 domains in ZO-1 mechano-sensing and dynamic interactions with the cytoskeleton and junctional ligands.
Collapse
Affiliation(s)
- Florian Rouaud
- Department of Cell Biology, Faculty of Sciences, University of Geneva , Geneva , Switzerland.,Institute of Genetics and Genomics of Geneva, University of Geneva , Geneva , Switzerland
| | - Ekaterina Vasileva
- Department of Cell Biology, Faculty of Sciences, University of Geneva , Geneva , Switzerland.,Institute of Genetics and Genomics of Geneva, University of Geneva , Geneva , Switzerland
| | - Domenica Spadaro
- Department of Cell Biology, Faculty of Sciences, University of Geneva , Geneva , Switzerland.,Institute of Genetics and Genomics of Geneva, University of Geneva , Geneva , Switzerland
| | - Sachiko Tsukita
- Strategic Innovation and Research Center, Teikyo University , Tokyo , Japan.,Graduate School of Frontier Biosciences, Osaka University , Osaka , Japan
| | - Sandra Citi
- Department of Cell Biology, Faculty of Sciences, University of Geneva , Geneva , Switzerland.,Institute of Genetics and Genomics of Geneva, University of Geneva , Geneva , Switzerland
| |
Collapse
|
126
|
Konishi S, Yano T, Tanaka H, Mizuno T, Kanoh H, Tsukita K, Namba T, Tamura A, Yonemura S, Gotoh S, Matsumoto H, Hirai T, Tsukita S. Vinculin is critical for the robustness of the epithelial cell sheet paracellular barrier for ions. Life Sci Alliance 2019; 2:2/4/e201900414. [PMID: 31399484 PMCID: PMC6689668 DOI: 10.26508/lsa.201900414] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 07/23/2019] [Accepted: 07/24/2019] [Indexed: 12/12/2022] Open
Abstract
Vinculin in the apical junctional complex maintains the paracellular barrier function specifically for ions, but not for large solutes, by buffering mechanical fluctuations. The paracellular barrier function of tight junctions (TJs) in epithelial cell sheets is robustly maintained against mechanical fluctuations, by molecular mechanisms that are poorly understood. Vinculin is an adaptor of a mechanosensory complex at the adherens junction. Here, we generated vinculin KO Eph4 epithelial cells and analyzed their confluent cell-sheet properties. We found that vinculin is dispensable for the basic TJ structural integrity and the paracellular barrier function for larger solutes. However, vinculin is indispensable for the paracellular barrier function for ions. In addition, TJs stochastically showed dynamically distorted patterns in vinculin KO cell sheets. These KO phenotypes were rescued by transfecting full-length vinculin and by relaxing the actomyosin tension with blebbistatin, a myosin II ATPase activity inhibitor. Our findings indicate that vinculin resists mechanical fluctuations to maintain the TJ paracellular barrier function for ions in epithelial cell sheets.
Collapse
Affiliation(s)
- Satoshi Konishi
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.,Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Tomoki Yano
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hiroo Tanaka
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.,Department of Pharmacology, Teikyo University, Tokyo, Japan.,Strategic Innovation and Research Center, Teikyo University, Tokyo, Japan
| | - Tomoaki Mizuno
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hatsuho Kanoh
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Kazuto Tsukita
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.,Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Toshinori Namba
- Graduate School of Arts and Sciences, Tokyo University, Tokyo, Japan
| | - Atsushi Tamura
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.,Department of Pharmacology, Teikyo University, Tokyo, Japan.,Strategic Innovation and Research Center, Teikyo University, Tokyo, Japan
| | - Shigenobu Yonemura
- Department of Cell Biology, Tokushima University Graduate School of Medical Science, Tokushima, Japan.,Laboratory for Ultrastructural Research, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Shimpei Gotoh
- Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.,Department of Drug Discovery for Lung Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Hisako Matsumoto
- Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Toyohiro Hirai
- Department of Respiratory Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Sachiko Tsukita
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan .,Strategic Innovation and Research Center, Teikyo University, Tokyo, Japan
| |
Collapse
|
127
|
Grauso M, Lan A, Andriamihaja M, Bouillaud F, Blachier F. Hyperosmolar environment and intestinal epithelial cells: impact on mitochondrial oxygen consumption, proliferation, and barrier function in vitro. Sci Rep 2019; 9:11360. [PMID: 31388052 PMCID: PMC6684637 DOI: 10.1038/s41598-019-47851-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 07/22/2019] [Indexed: 01/01/2023] Open
Abstract
The aim of the present study was to elucidate the in vitro short-term (2-h) and longer-term (24-h) effects of hyperosmolar media (500 and 680 mOsm/L) on intestinal epithelial cells using the human colonocyte Caco-2 cell line model. We found that a hyperosmolar environment slowed down cell proliferation compared to normal osmolarity (336 mOsm/L) without inducing cell detachment or necrosis. This was associated with a transient reduction of cell mitochondrial oxygen consumption, increase in proton leak, and decrease in intracellular ATP content. The barrier function of Caco-2 monolayers was also transiently affected since increased paracellular apical-to-basal permeability and modified electrolyte permeability were measured, allowing partial equilibration of the trans-epithelial osmotic difference. In addition, hyperosmotic stress induced secretion of the pro-inflammatory cytokine IL-8. By measuring expression of genes involved in energy metabolism, tight junction forming, electrolyte permeability and intracellular signaling, different response patterns to hyperosmotic stress occurred depending on its intensity and duration. These data highlight the potential impact of increased luminal osmolarity on the intestinal epithelium renewal and barrier function and point out some cellular adaptive capacities towards luminal hyperosmolar environment.
Collapse
Affiliation(s)
- Marta Grauso
- UMR PNCA, AgroParisTech, INRA, Université Paris-Saclay, 75005, Paris, France.
| | - Annaïg Lan
- UMR PNCA, AgroParisTech, INRA, Université Paris-Saclay, 75005, Paris, France
| | | | - Frédéric Bouillaud
- Institut Cochin, INSERM U1016, CNRS UMR8104, Université Paris Descartes, 75014, Paris, France
| | - François Blachier
- UMR PNCA, AgroParisTech, INRA, Université Paris-Saclay, 75005, Paris, France
| |
Collapse
|
128
|
Boschetti E, Accarino A, Malagelada C, Malagelada JR, Cogliandro RF, Gori A, Tugnoli V, Giancola F, Bianco F, Bonora E, Clavenzani P, Volta U, Caio G, Sternini C, Stanghellini V, Azpiroz F, Giorgio RD. Gut epithelial and vascular barrier abnormalities in patients with chronic intestinal pseudo-obstruction. Neurogastroenterol Motil 2019; 31:e13652. [PMID: 31144425 PMCID: PMC6639131 DOI: 10.1111/nmo.13652] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 04/30/2019] [Accepted: 05/18/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND Chronic intestinal pseudo-obstruction (CIPO) is a rare condition due to severe impairment of gut motility responsible for recurrent subocclusive episodes. Although neuromuscular-glial-ICC abnormalities represent the main pathogenetic mechanism, the pathophysiology of CIPO remains poorly understood. Intestinal epithelial and vascular endothelial barrier (IEVB) abnormalities can contribute to neuroepithelial changes by allowing passage of harmful substances. METHODS To test retrospectively whether IEVB defects occur in patients with CIPO, we measured the jejunal protein expression of the major tight junction (TJ) components. CIPO patients were subdivided according to gut neuromuscular histopathology: apparently normal (AN); with inflammation (INF); or with degenerative alterations (DEG). The presence of occludin/claudin oligomers (index of TJ assembly), the amount of occludin, claudin-4, and zonula occludens-1 (ZO-1), and the expression of vasoactive intestinal polypeptide (VIP) and glial fibrillary acidic protein (GFAP) immunoreactivities were evaluated on jejunal full-thickness biopsies using Western blot. KEY RESULTS Oligomers were absent in the 73% of CIPO. Total occludin decreased in CIPO with AN and INF changes. Claudin-4 was upregulated in CIPO with INF and DEG features. ZO-1 and VIP expression decreased selectively in DEG group. GFAP increased in CIPO regardless the histopathological phenotype. CONCLUSIONS & INFERENCES The absence of oligomers demonstrated in our study suggests that IEBV is altered in CIPO. The mechanism leading to oligomerization is occludin-dependent in AN and INF, whereas is ZO-1-dependent in DEG. Our study provides support to IEVB abnormalities contributing to CIPO clinical and histopathological features.
Collapse
Affiliation(s)
- Elisa Boschetti
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Anna Accarino
- Digestive System Research Unit, University Hospital Vall d’Hebron; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)
| | - Carolina Malagelada
- Digestive System Research Unit, University Hospital Vall d’Hebron; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)
| | - Juan R. Malagelada
- Digestive System Research Unit, University Hospital Vall d’Hebron; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)
| | | | - Alessandra Gori
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Vitaliano Tugnoli
- Department of Biomedical and Neuro Motor Sciences, University of Bologna, Bologna, Italy
| | - Fiorella Giancola
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Francesca Bianco
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Elena Bonora
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Paolo Clavenzani
- Department of Veterinary Medicine, University of Bologna, Ozzano, Italy
| | - Umberto Volta
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Giacomo Caio
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Catia Sternini
- Digestive-Disease-Division, Departments of Medicine and Neurobiology, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, USA
| | | | - Fernando Azpiroz
- Digestive System Research Unit, University Hospital Vall d’Hebron; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)
| | - Roberto De Giorgio
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy,Corresponding Author: Roberto De Giorgio, Department of Medical Sciences, Internal Medicine Unit, University of Ferrara, St. Anna Hospital, Via A. Moro, 8 - 44124 Cona, Ferrara, Italy, Tel.: +39 - 0532 - 236.631 -
| |
Collapse
|
129
|
He W, Wang Y, Wang P, Wang F. Intestinal barrier dysfunction in severe burn injury. BURNS & TRAUMA 2019; 7:24. [PMID: 31372365 PMCID: PMC6659221 DOI: 10.1186/s41038-019-0162-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 05/30/2019] [Indexed: 12/24/2022]
Abstract
Severe burn injury is often accompanied by intestinal barrier dysfunction, which is closely associated with post-burn shock, bacterial translocation, systemic inflammatory response syndrome, hypercatabolism, sepsis, multiple organ dysfunction syndrome, and other complications. The intestinal epithelium forms a physical barrier that separates the intestinal lumen from the internal milieu, in which the tight junction plays a principal role. It has been well documented that after severe burn injury, many factors such as stress, ischemia/hypoxia, proinflammatory cytokines, and endotoxins can induce intestinal barrier dysfunction via multiple signaling pathways. Recent advances have provided new insights into the mechanisms and the therapeutic strategies of intestinal epithelial barrier dysfunction associated with severe burn injury. In this review, we will describe the current knowledge of the mechanisms involved in intestinal barrier dysfunction in response to severe burn injury and the emerging therapies for treating intestinal barrier dysfunction following severe burn injury.
Collapse
Affiliation(s)
- Wen He
- State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 China
| | - Yu Wang
- Department of Gastroenterology, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 China
| | - Pei Wang
- State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 China
| | - Fengjun Wang
- State Key Laboratory of Trauma, Burns, and Combined Injury, Institute of Burn Research, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038 China
| |
Collapse
|
130
|
Awadia S, Huq F, Arnold TR, Goicoechea SM, Sun YJ, Hou T, Kreider-Letterman G, Massimi P, Banks L, Fuentes EJ, Miller AL, Garcia-Mata R. SGEF forms a complex with Scribble and Dlg1 and regulates epithelial junctions and contractility. J Cell Biol 2019; 218:2699-2725. [PMID: 31248911 PMCID: PMC6683736 DOI: 10.1083/jcb.201811114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/18/2019] [Accepted: 04/12/2019] [Indexed: 01/15/2023] Open
Abstract
The canonical Scribble polarity complex is implicated in regulation of epithelial junctions and apical polarity. Here, we show that SGEF, a RhoG-specific GEF, forms a ternary complex with Scribble and Dlg1, two members of the Scribble complex. SGEF targets to apical junctions in a Scribble-dependent fashion and functions in the regulation of actomyosin-based contractility and barrier function at tight junctions as well as E-cadherin-mediated formation of adherens junctions. Surprisingly, SGEF does not control the establishment of polarity. However, in 3D cysts, SGEF regulates the formation of a single open lumen. Interestingly, SGEF's nucleotide exchange activity regulates the formation and maintenance of adherens junctions, and in cysts the number of lumens formed, whereas SGEF's scaffolding activity is critical for regulation of actomyosin contractility and lumen opening. We propose that SGEF plays a key role in coordinating junctional assembly and actomyosin contractility by bringing together Scribble and Dlg1 and targeting RhoG activation to cell-cell junctions.
Collapse
Affiliation(s)
- Sahezeel Awadia
- Department of Biological Sciences, The University of Toledo, Toledo, OH
| | - Farah Huq
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Torey R Arnold
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | | | - Young Joo Sun
- Department of Biochemistry, University of Iowa, Iowa City, IA
| | - Titus Hou
- Department of Biochemistry, University of Iowa, Iowa City, IA
| | | | - Paola Massimi
- International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Lawrence Banks
- International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | | | - Ann L Miller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | | |
Collapse
|
131
|
Tervonen A, Ihalainen TO, Nymark S, Hyttinen J. Structural dynamics of tight junctions modulate the properties of the epithelial barrier. PLoS One 2019; 14:e0214876. [PMID: 30964903 PMCID: PMC6456171 DOI: 10.1371/journal.pone.0214876] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/21/2019] [Indexed: 01/09/2023] Open
Abstract
Tight junctions are dynamic structures that are crucial in establishing the diffusion and electrical barrier of epithelial monolayers. Dysfunctions in the tight junctions can impede this barrier function and lead to many pathological conditions. Unfortunately, detailed understanding of the non-specific permeation pathway through the tight junctions, the so-called leak pathway, is lacking. We created computational models of the leak pathway to describe the two main barrier measures, molecular permeability and transepithelial electric resistance while using common structural dynamics. Our results showed that the proposed alternatives for the leak pathway, the bicellular strand opening dynamics and the tricellular pores, contribute together with distinct degrees, depending on the epithelium. The models can also capture changes in the tight junction barrier caused by changes in tight junction protein composition. In addition, we observed that the molecular permeability was markedly more sensitive to changes in the tight junction structure and strand dynamics compared with transepithelial electric resistance. The results highlight that our model creates a good methodological framework to integrate knowledge on the tight junction structure as well as to provide insights and tools to advance tight junction research.
Collapse
Affiliation(s)
- Aapo Tervonen
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
- * E-mail:
| | - Teemu O. Ihalainen
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
| | - Soile Nymark
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
| | - Jari Hyttinen
- Faculty of Medicine and Health Technology and BioMediTech Institute, Tampere University, Tampere, Finland
| |
Collapse
|
132
|
Hesse-Macabata J, Morgner B, Morgenstern S, Grimm MO, Elsner P, Hipler UC, Wiegand C. Innate immune response of human epidermal keratinocytes and dermal fibroblasts to in vitro incubation of Trichophyton benhamiae DSM 6916. J Eur Acad Dermatol Venereol 2019; 33:1177-1188. [PMID: 30720896 DOI: 10.1111/jdv.15472] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/14/2019] [Indexed: 12/25/2022]
Abstract
BACKGROUND Superficial cutaneous infection caused by the zoophilic dermatophyte Trichophyton benhamiae is often associated with a highly inflammatory immune response. As non-professional immune cells, epidermal keratinocytes and dermal fibroblasts contribute to the first line of defence by producing pro-inflammatory cytokines and antimicrobial peptides (AMP). OBJECTIVE Purpose of this study was to gain a deeper understanding of the pathogenesis and the fungal-host interaction as not much is known about the innate immune response of these cutaneous cells against T. benhamiae. METHODS Using a dermatophytosis model of fibroblasts and keratinocytes incubated with T. benhamiae DSM 6916, analyses included determination of cell viability and cytotoxicity, effects on the innate immune response including expression and secretion of pro-inflammatory cytokines/chemokines and expression of AMP, as well as alterations of genes involved in cell adhesion. RESULTS Trichophyton benhamiae DSM 6916 infection led to severe cell damage and direct induction of a broad spectrum of pro-inflammatory cytokines and chemokines in both cutaneous cells. Only keratinocytes differentially up-regulated AMP genes expression after T. benhamiae DSM 6916 infection. Expression of AMPs in fibroblasts was not inducible by fungal infection, whereas their absences potentially contributed to a continuous increase in the fungal biomass on fibroblasts, which in turn was reduced in keratinocytes possibly due to the antimicrobial actions of induced AMPs. On mRNA level, T. benhamiae DSM 6916 infection altered cell-cell contact proteins in keratinocytes, indicating that targeting specific cell-cell adhesion proteins might be part of dermatophytes' virulence strategy. CONCLUSION This study showed that in addition to immune cells, keratinocytes and fibroblasts could participate in antimicrobial defence against an exemplary infection with T. benhamiae DSM 6916.
Collapse
Affiliation(s)
- J Hesse-Macabata
- Department of Dermatology, Jena University Hospital, Jena, Germany
| | - B Morgner
- Department of Dermatology, Jena University Hospital, Jena, Germany
| | - S Morgenstern
- Department of Urology, Jena University Hospital, Jena, Germany
| | - M O Grimm
- Department of Urology, Jena University Hospital, Jena, Germany
| | - P Elsner
- Department of Dermatology, Jena University Hospital, Jena, Germany
| | - U C Hipler
- Department of Dermatology, Jena University Hospital, Jena, Germany
| | - C Wiegand
- Department of Dermatology, Jena University Hospital, Jena, Germany
| |
Collapse
|
133
|
Rho Flares Repair Local Tight Junction Leaks. Dev Cell 2019; 48:445-459.e5. [PMID: 30773490 DOI: 10.1016/j.devcel.2019.01.016] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 11/12/2018] [Accepted: 01/17/2019] [Indexed: 12/29/2022]
Abstract
Tight junctions contribute to epithelial barrier function by selectively regulating the quantity and type of molecules that cross the paracellular barrier. Experimental approaches to evaluate the effectiveness of tight junctions are typically global, tissue-scale measures. Here, we introduce Zinc-based Ultrasensitive Microscopic Barrier Assay (ZnUMBA), which we used in Xenopus laevis embryos to visualize short-lived, local breaches in epithelial barrier function. These breaches, or leaks, occur as cell boundaries elongate, correspond to visible breaks in the tight junction, and are followed by transient localized Rho activation, or Rho flares. We discovered that Rho flares restore barrier function by driving concentration of tight junction proteins through actin polymerization and ROCK-mediated localized contraction of the cell boundary. We conclude that Rho flares constitute a damage control mechanism that reinstates barrier function when tight junctions become locally compromised because of normally occurring changes in cell shape and tissue tension.
Collapse
|
134
|
Wang Y, Li Y, Zou J, Polster SP, Lightle R, Moore T, Dimaano M, He TC, Weber CR, Awad IA, Shen L. The cerebral cavernous malformation disease causing gene KRIT1 participates in intestinal epithelial barrier maintenance and regulation. FASEB J 2019; 33:2132-2143. [PMID: 30252535 PMCID: PMC6338648 DOI: 10.1096/fj.201800343r] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 08/27/2018] [Indexed: 01/15/2023]
Abstract
Epithelial barrier maintenance and regulation requires an intact perijunctional actomyosin ring underneath the cell-cell junctions. By searching for known factors affecting the actin cytoskeleton, we identified Krev interaction trapped protein 1 (KRIT1) as a major regulator for epithelial barrier function through multiple mechanisms. KRIT1 is expressed in both small intestinal and colonic epithelium, and KRIT1 knockdown in differentiated Caco-2 intestinal epithelium decreases epithelial barrier function and increases cation selectivity. KRIT1 knockdown abolished Rho-associated protein kinase-induced and myosin II motor inhibitor-induced barrier loss by limiting both small and large molecule permeability but did not affect myosin light chain kinase-induced increases in epithelial barrier function. These data suggest that KRIT1 participates in Rho-associated protein kinase- and myosin II motor-dependent (but not myosin light chain kinase-dependent) epithelial barrier regulation. KRIT1 knockdown exacerbated low-dose TNF-induced barrier loss, along with increased cleaved caspase-3 production. Both events are blocked by pan-caspase inhibition, indicating that KRIT1 regulates TNF-induced barrier loss through limiting epithelial apoptosis. These data indicate that KRIT1 controls epithelial barrier maintenance and regulation through multiple pathways, suggesting that KRIT1 mutation in cerebral cavernous malformation disease may alter epithelial function and affect human health.-Wang, Y., Li, Y., Zou, J., Polster, S. P., Lightle, R., Moore, T., Dimaano, M., He, T.-C., Weber, C. R., Awad, I. A., Shen, L. The cerebral cavernous malformation disease causing gene KRIT1 participates in intestinal epithelial barrier maintenance and regulation.
Collapse
Affiliation(s)
- Yitang Wang
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
- Department of Pathology, The University of Chicago, Chicago, Illinois, USA
| | - Ye Li
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
- Department of Pathology, The University of Chicago, Chicago, Illinois, USA
| | - Jinjing Zou
- Department of Pathology, The University of Chicago, Chicago, Illinois, USA
- Department of Pulmonary and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Sean P. Polster
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
| | - Rhonda Lightle
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
| | - Thomas Moore
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
| | - Matthew Dimaano
- Department of Medicine, The University of Chicago, Chicago, Illinois, USA; and
| | - Tong-Chuan He
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago, Chicago, Illinois, USA
| | | | - Issam A. Awad
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
| | - Le Shen
- Section of Neurosurgery, Department of Surgery, The University of Chicago, Chicago, Illinois, USA
- Department of Pathology, The University of Chicago, Chicago, Illinois, USA
| |
Collapse
|
135
|
Homoectoine Protects Against Colitis by Preventing a Claudin Switch in Epithelial Tight Junctions. Dig Dis Sci 2019; 64:409-420. [PMID: 30269272 DOI: 10.1007/s10620-018-5309-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 09/26/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND Inflammatory bowel diseases (IBD) are multifactorial disorders affecting millions of people worldwide with alarmingly increasing incidences every year. Dysfunction of the intestinal epithelial barrier is associated with IBD pathogenesis, and therapies include anti-inflammatory drugs that enhance intestinal barrier function. However, these drugs often have adverse side effects thus warranting the search for alternatives. Compatible solutes such as bacterial ectoines stabilize cell membranes and proteins. AIM To unravel whether ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) and homoectoine (4,5,6,7-tetrahydro-2-methyl-1H-(1,3)-diazepine-4-carboxylic acid), a synthetic derivative of ectoine, have beneficial effects during dextran sulfate sodium (DSS)-induced colitis in mice. METHODS/RESULTS We found that the disease activity index was significantly reduced by both ectoines. DSS-induced edema formation, epithelial permeability, leukocyte recruitment and tissue damage were reduced by ectoine and homoectoine, with the latter having stronger effects. Interestingly, the claudin switch usually observed during colitis (decreased expression of claudin-1 and increased expression of the leaky claudin-2) was completely prevented by homoectoine, whereas ectoine only reduced claudin-2 expression. Concomitantly, only homoectoine ameliorated the drop in transepithelial electrical resistance induced by IFN-γ and TNF-α in Caco-2 cells. Both ectoines inhibited loss of ZO-1 and occludin and prevented IFN-γ/TNF-α-induced increased paracellular flux of 4 kDa FITC-dextran in vitro. Moreover, both ectoines reduced expression of pro-inflammatory cytokines and oxidative stress during colitis. CONCLUSION While both ectoine and homoectoine have protective effects on the epithelial barrier during inflammation, only homoectoine completely prevented the inflammatory claudin switch in tight junctions. Thus, homoectoine may serve as diet supplement in IBD patients to reach or extend remission.
Collapse
|
136
|
Bashir M, Meddings J, Alshaikh A, Jung D, Le K, Amin R, Ratakonda S, Sharma S, Granja I, Satti M, Asplin J, Hassan H. Enhanced gastrointestinal passive paracellular permeability contributes to the obesity-associated hyperoxaluria. Am J Physiol Gastrointest Liver Physiol 2019; 316:G1-G14. [PMID: 30307745 PMCID: PMC6383380 DOI: 10.1152/ajpgi.00266.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Most kidney stones (KS) are composed of calcium oxalate and small increases in urine oxalate enhance the stone risk. Obesity is a risk factor for KS, and urinary oxalate excretion increases with increased body size. We previously established the obese ob/ob ( ob) mice as a model (3.3-fold higher urine oxalate) to define the pathogenesis of obesity-associated hyperoxaluria (OAH). The purpose of this study was to test the hypothesis that the obesity-associated enhanced small intestinal paracellular permeability contributes to OAH by increasing passive paracellular intestinal oxalate absorption. ob Mice have significantly higher jejunal (1.6-fold) and ileal (1.4-fold) paracellular oxalate absorption ex vivo and significantly higher (5-fold) urine [13C]oxalate following oral gavage with [13C]oxalate, indicating increased intestinal oxalate absorption in vivo. The observation of higher oxalate absorption in vivo compared with ex vivo suggests the possibility of increased paracellular permeability along the entire gut. Indeed, ob mice have significantly higher fractions of the administered sucrose (1.7-fold), lactulose (4.4-fold), and sucralose (3.1-fold) excreted in the urine, reflecting increased gastric, small intestinal, and colonic paracellular permeability, respectively. The ob mice have significantly reduced gastrointestinal occludin, zonula occludens-1, and claudins-1 and -3 mRNA and total protein expression. Proinflammatory cytokines and oxidative stress, which are elevated in obesity, significantly enhanced paracellular intestinal oxalate absorption in vitro and ex vivo. We conclude that obese mice have significantly higher intestinal oxalate absorption and enhanced gastrointestinal paracellular permeability in vivo, which would likely contribute to the pathogenesis of OAH, since there is a transepithelial oxalate concentration gradient to drive paracellular intestinal oxalate absorption. NEW & NOTEWORTHY This study shows that the obese ob/ob mice have significantly increased gastrointestinal paracellular oxalate absorption and remarkably enhanced paracellular permeability along the entire gut in vivo, which are likely mediated by the obesity-associated increased systemic and intestinal inflammation and oxidative stress. A transepithelial oxalate concentration gradient driving gastrointestinal paracellular oxalate absorption exists, and therefore, our novel findings likely contribute to the hyperoxaluria observed in the ob/ob mice and hence to the pathogenesis of obesity-associated hyperoxaluria.
Collapse
Affiliation(s)
- Mohamed Bashir
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Jon Meddings
- 2Department of Surgery, University of Calgary, Calgary, Alberta, Canada
| | - Altayeb Alshaikh
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Daniel Jung
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Kim Le
- 2Department of Surgery, University of Calgary, Calgary, Alberta, Canada
| | - Ruhul Amin
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| | | | - Sapna Sharma
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| | - Ignacio Granja
- 3Litholink Corporation, Laboratory Corporation of America Holdings, Chicago, Illinois
| | - Mustafa Satti
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| | - John Asplin
- 3Litholink Corporation, Laboratory Corporation of America Holdings, Chicago, Illinois
| | - Hatim Hassan
- 1Department of Medicine, The University of Chicago, Chicago, Illinois
| |
Collapse
|
137
|
Peng Y, Li H, Chen D. Silencing astrocyte elevated gene-1 attenuates lipopolysaccharide-induced inflammation and mucosal barrier injury in NCM460 cells by suppressing the activation of NLRP3 inflammasome. Cell Biol Int 2018; 43:56-64. [PMID: 30489008 DOI: 10.1002/cbin.11078] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 11/24/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Yang Peng
- Emergency Department; Jingmen No. 1 People's Hospital; No. 168 Xiangshan Road Jingmen Hubei Province 448000 China
| | - Hongyan Li
- Department of Thyroid and Breast Surgery; Jingmen No. 1 People's Hospital; No. 168 Xiangshan Road Jingmen Hubei Province 448000 China
| | - Dandan Chen
- Department of General Surgery; Jingmen No. 1 People's Hospital; No. 168 Xiangshan Road Jingmen Hubei Province 448000 China
| |
Collapse
|
138
|
Hua Y, Yan K, Wan C. Clever Cooperation: Interactions Between EspF and Host Proteins. Front Microbiol 2018; 9:2831. [PMID: 30524410 PMCID: PMC6262023 DOI: 10.3389/fmicb.2018.02831] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/05/2018] [Indexed: 12/12/2022] Open
Abstract
EspF is a central effector protein of enterohemorrhagic Escherichia coli (EHEC), enteropathogenic E. coli (EPEC), and Citrobacter rodentium (CR) that is secreted through the type III secretion system to host cells. The interaction between EspF and host proteins plays an important role in bacterial pathogenesis. EspF protein binds to host SNX9 and N-WASP proteins to promote the colonization of pathogenic bacteria in intestinal epithelial cells; combines with cytokeratin 18, actin, 14-3-3ζ, Arp2/3, profilin, and ZO-1 proteins to intervene in the redistribution of intermediate filaments, the rearrangement of actin, and the disruption of tight junctions; acts together with Abcf2 to boost host cell intrinsic apoptosis; and collaborates with Anxa6 protein to inhibit phagocytosis. The interaction between EspF and host proteins is key to the pathogenic mechanism of EHEC and EPEC. Here, we review how EspF protein functions through interactions with these 10 host proteins and contributes to the pathogenicity of EHEC/EPEC.
Collapse
Affiliation(s)
- Ying Hua
- Department of Microbiology, School of Public Health, Southern Medical University, Guangzhou, China.,Key Laboratory of Tropical Disease Research of Guangdong Province, Guangzhou, China
| | - Kaina Yan
- Department of Microbiology, School of Public Health, Southern Medical University, Guangzhou, China.,Key Laboratory of Tropical Disease Research of Guangdong Province, Guangzhou, China
| | - Chengsong Wan
- Department of Microbiology, School of Public Health, Southern Medical University, Guangzhou, China.,Key Laboratory of Tropical Disease Research of Guangdong Province, Guangzhou, China
| |
Collapse
|
139
|
Ortega-Olvera JM, Winkler R, Quintanilla-Vega B, Shibayama M, Chávez-Munguía B, Martín-Tapia D, Alarcón L, González-Mariscal L. The organophosphate pesticide methamidophos opens the blood-testis barrier and covalently binds to ZO-2 in mice. Toxicol Appl Pharmacol 2018; 360:257-272. [PMID: 30291936 DOI: 10.1016/j.taap.2018.10.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 09/21/2018] [Accepted: 10/01/2018] [Indexed: 12/12/2022]
Abstract
Methamidophos (MET) is an organophosphate (OP) pesticide widely used in agriculture in developing countries. MET causes adverse effects in male reproductive function in humans and experimental animals, but the underlying mechanisms remain largely unknown. We explored the effect of MET on mice testes (5 mg/kg/day/4 days), finding that this pesticide opens the blood-testis barrier and perturbs spermatogenesis, generating the appearance of immature germ cells in the epididymis. In the seminiferous tubules, MET treatment changed the level of expression or modified the stage-specific localization of tight junction (TJ) proteins ZO-1, ZO-2, occludin, and claudin-3. In contrast, claudin-11 was barely altered. MET also modified the shape of claudin-11, and ZO-2 at the cell border, from a zigzag to a more linear pattern. In addition, MET diminished the expression of ZO-2 in spermatids present in seminiferous tubules, induced the phosphorylation of ZO-2 and occludin in testes and reduced the interaction between these proteins assessed by co-immunoprecipitation. MET formed covalent bonds with ZO-2 in serine, tyrosine and lysine residues. The covalent modifications formed on ZO-2 at putative phosphorylation sites might interfere with ZO-2 interaction with regulatory molecules and other TJ proteins. MET bonds formed at ZO-2 ubiquitination sites likely interfere with ZO-2 degradation and TJ sealing, based on results obtained in cultured epithelial cells transfected with ZO-2 mutated at a MET target lysine residue. Our results shed light on MET male reproductive toxicity and are important to improve regulations regarding the use of OP pesticides and to protect the health of agricultural workers.
Collapse
Affiliation(s)
| | - Robert Winkler
- Department of Biotechnology and Biochemistry, Cinvestav, Irapuato 36824, Mexico; Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | | | - Mineko Shibayama
- Department of Infectomics and Molecular Pathogenesis, Cinvestav, Mexico City 07360, Mexico
| | - Bibiana Chávez-Munguía
- Department of Infectomics and Molecular Pathogenesis, Cinvestav, Mexico City 07360, Mexico
| | - Dolores Martín-Tapia
- Department of Physiology, Biophysics and Neuroscience, Cinvestav, Mexico City 07360, Mexico
| | - Lourdes Alarcón
- Department of Physiology, Biophysics and Neuroscience, Cinvestav, Mexico City 07360, Mexico
| | | |
Collapse
|
140
|
Odenwald MA, Choi W, Kuo WT, Singh G, Sailer A, Wang Y, Shen L, Fanning AS, Turner JR. The scaffolding protein ZO-1 coordinates actomyosin and epithelial apical specializations in vitro and in vivo. J Biol Chem 2018; 293:17317-17335. [PMID: 30242130 DOI: 10.1074/jbc.ra118.003908] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 09/14/2018] [Indexed: 12/21/2022] Open
Abstract
Polarized epithelia assemble into sheets that compartmentalize organs and generate tissue barriers by integrating apical surfaces into a single, unified structure. This tissue organization is shared across organs, species, and developmental stages. The processes that regulate development and maintenance of apical epithelial surfaces are, however, undefined. Here, using an intestinal epithelial-specific knockout (KO) mouse and cultured epithelial cells, we show that the tight junction scaffolding protein zonula occludens-1 (ZO-1) is essential for development of unified apical surfaces in vivo and in vitro We found that U5 and GuK domains of ZO-1 are necessary for proper apical surface assembly, including organization of microvilli and cortical F-actin; however, direct interactions with F-actin through the ZO-1 actin-binding region (ABR) are not required. ZO-1 lacking the PDZ1 domain, which binds claudins, rescued apical structure in ZO-1-deficient epithelia, but not in cells lacking both ZO-1 and ZO-2, suggesting that heterodimerization with ZO-2 restores PDZ1-dependent ZO-1 interactions that are vital to apical surface organization. Pharmacologic F-actin disruption, myosin II motor inhibition, or dynamin inactivation restored apical epithelial structure in vitro and in vivo, indicating that ZO-1 directs epithelial organization by regulating actomyosin contraction and membrane traffic. We conclude that multiple ZO-1-mediated interactions contribute to coordination of epithelial actomyosin function and genesis of unified apical surfaces.
Collapse
Affiliation(s)
| | - Wangsun Choi
- the Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, and
| | - Wei-Ting Kuo
- the Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, and
| | - Gurminder Singh
- From the Departments of Pathology and.,the Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, and
| | | | | | - Le Shen
- From the Departments of Pathology and.,Surgery, University of Chicago, Chicago, Illinois 60637
| | - Alan S Fanning
- the Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Jerrold R Turner
- From the Departments of Pathology and .,the Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, and
| |
Collapse
|
141
|
Importance of integrity of cell-cell junctions for the mechanics of confluent MDCK II cells. Sci Rep 2018; 8:14117. [PMID: 30237412 PMCID: PMC6148251 DOI: 10.1038/s41598-018-32421-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 08/29/2018] [Indexed: 12/14/2022] Open
Abstract
Intercellular junctions are important mechanical couplers between cells in epithelial layers providing adhesion and intercellular communication. Regulation of the junctions occurs in cellular processes such as layer formation, epithelial-to-mesenchymal transition, embryogenesis, and cancer progression. Many studies addressed the role of force generation in cells for establishing lateral cell-cell junctions and the role of cellular force transmission in tissue formation and maintenance. Our atomic force microscopy- (AFM) based study shed light on the role of both, tight junctions and adherens junctions for the mechanical properties of individual epithelial cells that are part of a confluent monolayer. We found that tight junctions are important for the establishment of a functional barrier-forming layer but impairing them does not reduce the mechanical integrity of cells. Depletion of ZO-1 results in a weak increase in cortical tension. An opposite effect was observed for disruption of E-cadherin-mediated adherens junctions using DTT. Opening of adherens junctions leads to substantial alterations of cellular mechanics such as reduced overall stiffness, but these changes turned out to be reversible after re-establishing disulfide bridges in E-cadherin by removal of DTT. We found that regulatory mechanisms exist that preserve mechanical integrity during recovery of disrupted adherens junctions.
Collapse
|
142
|
A new meroterpenoid functions as an anti-tumor agent in hepatoma cells by downregulating mTOR activation and inhibiting EMT. Sci Rep 2018; 8:13152. [PMID: 30177727 PMCID: PMC6120861 DOI: 10.1038/s41598-018-31409-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/03/2018] [Indexed: 02/07/2023] Open
Abstract
Liver cancer, also known as primary liver cancer, is cancer that starts in the liver. JNU-144, a new meroterpenoid purified from Lithospermum erythrorhizon, has exhibited promising anticancer activity; however, the molecular mechanisms of action of JNU-144 on malignant cells remain unclear. Our studies revealed that JNU-144 suppressed cell viability and proliferation in hepatoma cells by downregulating mTOR activation. Meanwhile, JNU-144 activated the intrinsic apoptosis pathway and subsequently triggered apoptotic cell death in SMMC-7721 cells. We also found that JNU-144 inhibited the epithelial–mesenchymal transition in both SMMC-7721 and HepG2 cells through reprogramming of epithelial–mesenchymal transition (EMT)-related gene expression or regulating protein instability. These findings indicate that JNU-144 exerts potent anticancer activity in hepatoma cells and may be developed as a potential therapeutic drug.
Collapse
|
143
|
Li J, Zeng B, Hu X, Li Z, Zhang D, Yang G, Dai J, Zeng X. Protective Effects of Ginsenoside Rb1 against Blood-Brain Barrier Damage Induced by Human Immunodeficiency Virus-1 Tat Protein and Methamphetamine in Sprague-Dawley Rats. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2018; 46:551-566. [PMID: 29690789 DOI: 10.1142/s0192415x18500283] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Although antiretroviral therapy has helped to improve the lives of individuals infected with human immunodeficiency virus 1 (HIV-1), these patients are often still afflicted with HIV-1-associated neurocognitive disorders, which can lead to neurocognitive impairment and even dementia, and continue to hamper their quality of life. Methamphetamine abuse in HIV-1 patients poses a potential risk for HIV-associated neurocognitive disorders, because methamphetamine and HIV-1 proteins such as transactivator of transcription can synergistically damage the blood-brain barrier (BBB). In this study, we aimed to examine the effects of methamphetamine and HIV-1 Tat protein on the blood-brain barrier function and to determine whether ginsenoside Rb1 (GsRb1) plays a role in protecting the BBB. Sprague-Dawley rats were divided into four groups. The experimental groups received methamphetamine and HIV-1 Tat protein or both and the control group received saline or GsRb1 pretreatment. Oxidative stress-related factors, tight junction (TJ) proteins, blood-brain barrier permeability, and morphological changes were recorded in each group. The results showed that the group treated with Methamphetamine[Formula: see text]Tat showed a significant change at the ultrastructural level and in the levels of oxidative stress-related factors, TJ proteins, and BBB permeability, suggesting that the BBB function was severely damaged by HIV-1 Tat and methamphetamine synergistically. However, malondialdehyde levels and BBB permeability were lower and the oxidative stress-related factors superoxide dismutase and glutathione were higher in the GsRb1-treated group than in the Methamphetamine[Formula: see text]Tat-treated group, indicating that GsRb1 can protect the BBB against the toxic effects of HIV-1 Tat and methamphetamine. These results show that GsRb1 may offer a potential therapeutic option for patients with HIV-associated neurocognitive disorders or other neurodegenerative diseases.
Collapse
Affiliation(s)
- Juan Li
- * Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Kunming, Yunnan, P. R. China
| | - Bairui Zeng
- † School of Forensic Medicine, Kunming Medical University, Kunming, Yunnan, P. R. China.,‡ Wuhua Branch of Kunming Public Security Bureau, Kunming, Yunnan, P. R. China
| | - Xiao Hu
- † School of Forensic Medicine, Kunming Medical University, Kunming, Yunnan, P. R. China
| | - Zhen Li
- † School of Forensic Medicine, Kunming Medical University, Kunming, Yunnan, P. R. China
| | - Dongxian Zhang
- † School of Forensic Medicine, Kunming Medical University, Kunming, Yunnan, P. R. China
| | - Genmeng Yang
- † School of Forensic Medicine, Kunming Medical University, Kunming, Yunnan, P. R. China
| | - Jiejie Dai
- * Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, The Chinese Academy of Medical Science and Peking Union Medical College, Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Kunming, Yunnan, P. R. China
| | - Xiaofeng Zeng
- † School of Forensic Medicine, Kunming Medical University, Kunming, Yunnan, P. R. China
| |
Collapse
|
144
|
Cheng RY, Li M, Li SS, He M, Yu XH, Shi L, He F. Vancomycin and ceftriaxone can damage intestinal microbiota and affect the development of the intestinal tract and immune system to different degrees in neonatal mice. Pathog Dis 2018; 75:4091429. [PMID: 28957452 DOI: 10.1093/femspd/ftx104] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 08/21/2017] [Indexed: 02/05/2023] Open
Abstract
This study aimed to determine how antibiotic-driven intestinal dysbiosis impairs the development and differentiation of the digestive tract and immune organs of host animals. BALB/C neonatal mice were orally administered ceftriaxone or vancomycin from postnatal day 1 to day 21 and sacrificed on day 21. The diversity and abundance of the intestinal bacteria, morphological changes and barrier function of intestinal tract, and the splenic CD4+CD25+Foxp3+ T cells were investigated. The gut microbiota and intestinal tissue were damaged, and the numbers of Ki67-, Muc2- and ZO-1-positive cells were significantly decreased in the antibiotic treatment groups. Furthermore, the administration of ceftriaxone, but not vancomycin, led to a significant reduction in the abundance of splenic CD4+CD25+Foxp3+ T cells. Each antibiotic caused intestinal dysbiosis and characteristically influenced the regeneration of intestinal epithelial cells, formation of the intestinal mucus layer and tight junctions, and differentiation of splenic Foxp3+ Treg cells of the neonatal mice before any clinical side effects were observed. The potent ability of each antibiotic to affect the makeup of intestinal commensal microbiota may be a key determinant of the spectrum of antibiotics and influence the health of the host animal, at least partly.
Collapse
Affiliation(s)
- Ru Yue Cheng
- Department of Nutrition, Food Hygiene and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| | - Ming Li
- Department of Nutrition, Food Hygiene and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| | - Shan Shan Li
- Department of Nutrition, Food Hygiene and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| | - Miao He
- Department of Nutrition, Food Hygiene and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| | - Xiao Hong Yu
- Department of Nutrition, Food Hygiene and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| | - Lei Shi
- Department of Nutrition, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| | - Fang He
- Department of Nutrition, Food Hygiene and Toxicology, West China School of Public Health, Sichuan University, Chengdu, Sichuan, 610041, P. R. China
| |
Collapse
|
145
|
Bilal S, Jaggi S, Janosevic D, Shah N, Teymour S, Voronina A, Watari J, Axis J, Amsler K. ZO-1 protein is required for hydrogen peroxide to increase MDCK cell paracellular permeability in an ERK 1/2-dependent manner. Am J Physiol Cell Physiol 2018; 315:C422-C431. [PMID: 29874107 DOI: 10.1152/ajpcell.00185.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hydrogen peroxide (H2O2) increases paracellular permeability of Madin-Darby canine kidney (MDCK) cells, but the mechanism mediating this effect remains unclear. Treatment of MDCK cells with H2O2 activated ERK 1/2. Inhibition of ERK 1/2 activation blocked the ability of H2O2 to increase paracellular permeability. Knockdown of zonula occludens-1 (ZO-1) protein but not occludin eliminated the ability of H2O2 to increase paracellular permeability. H2O2 treatment did not, however, affect the total cell content or contents of the Triton X-100-soluble and -insoluble fractions for occludin, ZO-1, or ZO-2. H2O2 treatment decreased the number of F-actin stress fibers in the basal portion of the cells. Similar to wild-type MDCK cells, H2O2 increased ERK 1/2 activation in ZO-1 knockdown and occludin knockdown cells. Inhibition of ERK 1/2 activation blocked the increase in paracellular permeability in occludin knockdown cells. ZO-1 knockdown cell paracellular permeability was regulated by PP1, an src inhibitor, indicating that the loss of response to H2O2 was not a general loss of the ability to regulate the paracellular barrier. Inhibition of myosin ATPase activity with blebbistatin increased paracellular permeability in ZO-1 knockdown cells but not in wild-type MDCK cells. H2O2 treatment sensitized wild-type MDCK cells to inhibition of myosin ATPase. Knockdown of TOCA-1 protein, which promotes formation of local branched actin networks, reproduced the effects of ZO-1 protein knockdown. These results demonstrate that H2O2 increases MDCK cell paracellular permeability through activation of ERK 1/2. This H2O2 action requires ZO-1 protein and TOCA-1 protein, suggesting involvement of the actin cytoskeleton.
Collapse
Affiliation(s)
- Sahar Bilal
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Shirin Jaggi
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Danielle Janosevic
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Nikita Shah
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Shereen Teymour
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Angelina Voronina
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Jessica Watari
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Josephine Axis
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| | - Kurt Amsler
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York
| |
Collapse
|
146
|
Regulation of Intestinal Epithelial Cells Properties and Functions by Amino Acids. BIOMED RESEARCH INTERNATIONAL 2018; 2018:2819154. [PMID: 29854738 PMCID: PMC5966675 DOI: 10.1155/2018/2819154] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/23/2018] [Accepted: 04/02/2018] [Indexed: 12/24/2022]
Abstract
Intestinal epithelial cells (IECs) line the surface of intestinal epithelium, where they play important roles in the digestion of food, absorption of nutrients, and protection of the human body from microbial infections, and others. Dysfunction of IECs can cause diseases. The development, maintenance, and functions of IECs are strongly influenced by external nutrition, such as amino acids. Amino acids play important roles in regulating the properties and functions of IECs. In this article, we briefly reviewed the current understanding of the roles of amino acids in the regulation of IECs' properties and functions in physiological state, including in IECs homeostasis (differentiation, proliferation, and renewal), in intestinal epithelial barrier structure and functions, and in immune responses. We also summarized some important findings on the effects of amino acids supplementation (e.g., glutamine and arginine) in restoring IECs' and intestine functions in some diseased states. These findings will further our understanding of the important roles of amino acids in the homeostasis of IECs and could potentially help identify novel targets and reagents for the therapeutic interventions of diseases associated with dysfunctional IECs.
Collapse
|
147
|
Aasen T, Johnstone S, Vidal-Brime L, Lynn KS, Koval M. Connexins: Synthesis, Post-Translational Modifications, and Trafficking in Health and Disease. Int J Mol Sci 2018; 19:ijms19051296. [PMID: 29701678 PMCID: PMC5983588 DOI: 10.3390/ijms19051296] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/20/2018] [Accepted: 04/21/2018] [Indexed: 02/06/2023] Open
Abstract
Connexins are tetraspan transmembrane proteins that form gap junctions and facilitate direct intercellular communication, a critical feature for the development, function, and homeostasis of tissues and organs. In addition, a growing number of gap junction-independent functions are being ascribed to these proteins. The connexin gene family is under extensive regulation at the transcriptional and post-transcriptional level, and undergoes numerous modifications at the protein level, including phosphorylation, which ultimately affects their trafficking, stability, and function. Here, we summarize these key regulatory events, with emphasis on how these affect connexin multifunctionality in health and disease.
Collapse
Affiliation(s)
- Trond Aasen
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, 08035 Barcelona, Spain.
| | - Scott Johnstone
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VI 22908, USA.
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TT, UK.
| | - Laia Vidal-Brime
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, 08035 Barcelona, Spain.
| | - K Sabrina Lynn
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
148
|
Lagha AB, Groeger S, Meyle J, Grenier D. Green tea polyphenols enhance gingival keratinocyte integrity and protect against invasion by Porphyromonas gingivalis. Pathog Dis 2018; 76:4961135. [DOI: 10.1093/femspd/fty030] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 04/03/2018] [Indexed: 12/15/2022] Open
Affiliation(s)
- Amel Ben Lagha
- Oral Ecology Research Group, Faculty of Dentistry, Université Laval, 2420 rue de la Terrasse, Quebec City, QC G1V 0A6, Canada
| | - Sabine Groeger
- Department of Periodontology, Justus-Liebig-University of Giessen, Schlangenzahl 14, Giessen 35392, Germany
| | - Joerg Meyle
- Department of Periodontology, Justus-Liebig-University of Giessen, Schlangenzahl 14, Giessen 35392, Germany
| | - Daniel Grenier
- Oral Ecology Research Group, Faculty of Dentistry, Université Laval, 2420 rue de la Terrasse, Quebec City, QC G1V 0A6, Canada
| |
Collapse
|
149
|
Garcia MA, Nelson WJ, Chavez N. Cell-Cell Junctions Organize Structural and Signaling Networks. Cold Spring Harb Perspect Biol 2018; 10:a029181. [PMID: 28600395 PMCID: PMC5773398 DOI: 10.1101/cshperspect.a029181] [Citation(s) in RCA: 262] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cell-cell junctions link cells to each other in tissues, and regulate tissue homeostasis in critical cell processes that include tissue barrier function, cell proliferation, and migration. Defects in cell-cell junctions give rise to a wide range of tissue abnormalities that disrupt homeostasis and are common in genetic abnormalities and cancers. Here, we discuss the organization and function of cell-cell junctions primarily involved in adhesion (tight junction, adherens junction, and desmosomes) in two different epithelial tissues: a simple epithelium (intestine) and a stratified epithelium (epidermis). Studies in these tissues reveal similarities and differences in the organization and functions of different cell-cell junctions that meet the requirements for the specialized functions of each tissue. We discuss cell-cell junction responses to genetic and environmental perturbations that provide further insights into their roles in maintaining tissue homeostasis.
Collapse
Affiliation(s)
- Miguel A Garcia
- Department of Biology, Stanford University, Stanford, California 94305
| | - W James Nelson
- Department of Biology, Stanford University, Stanford, California 94305
- Departments of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305
| | - Natalie Chavez
- Department of Biology, Stanford University, Stanford, California 94305
| |
Collapse
|
150
|
Zenker J, White MD, Gasnier M, Alvarez YD, Lim HYG, Bissiere S, Biro M, Plachta N. Expanding Actin Rings Zipper the Mouse Embryo for Blastocyst Formation. Cell 2018; 173:776-791.e17. [DOI: 10.1016/j.cell.2018.02.035] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/20/2017] [Accepted: 02/15/2018] [Indexed: 01/08/2023]
|